Process of producing textiles with calender finish permanent to washing and product thereof



Patented June 21, 1938 PATENT OFFICE PROCESS OF PRODUCING TEXTILES WITHCALENDER FINISH PERMANENT TO WASH- ING AND PRODUCT THEREOF ChristianBenet, Chur, Switzerland, assignor to the firm Raduncr & co. A.-G.,Horn, Switzerland No Drawing. Application October 4, 1934, Serial InSwitzerland October 14, 1933 3 Claims. (01. 91 -619) This inventionrelates to the production of improved textiles having calender finishpermanently fast to washing and the product thereof.

Hitherto, it was impossible to obtain calender 5 or stamping effects onfabrics in a satisfactory manner, so as to render the fabric fast toaftertreatments, as for example the normal washing. The texture impartedto the textile by calendering the same by pressing, stamping or lappingthe fibers automatically changes back to the original state by thefibers reassuming their previous form and relative disposition, whenswelling up by being wetted, soaped, steamed or ironed, whereby theeffect obtained on the fabric by means of the calender disappearsentirely or for the most part.

I have now found that a permanent finish can be obtained by fixing theeffects accruing from the calender treatment by means of resins adaptedto be hardened. This method ends in the surprising result that theartificial effects and the corresponding form and relative dispositionof the textile fibers produced by means of the calender are permanentlyretained also during washing such fabrics, provided that the resin hadbeen hardened.

It was also known before the present time that by incorporating in thefibers, that is, introducing into the interior thereof, natural orartificial resins or starting components thereof, in some cases, bysubsequently changing the structure of these substances chemically,effects can be obtained which, due to a hardening; that is an increaseof the resistivity against fiexion and of the elasticity of the fibers,promote the tendency of the fibers to reassume their original form upondeformation. The so-called methods of rendering fabrics resistiveagainst wrinkling are based on this knowledge.

In view of this state of the art, the fact that by aid of exterior andinterior deposits of this kind and by hardening the same, textilearticles can be arbitrarily compelled to change their surface or form soas to be adapted to permanently withstand the influence of soaking inthe wash, is a surprising and unexpected technical advance in the art.

Based on the prior knowledge of rendering textiles resistive againstcreasing and the relevant experience, one should have expected that allthe fibers of the material impregnated in this fashion would tend toreassume their original natural shape and relative dispositions and thusalso the surface texture of the material would be recovered, so that forexample all textile materials of a smooth surface texture would regaintheir original smoothness by the wrinkles in the surface disappearing.This is, however, not so, not even after washing or the like, as thematerial retains any surface texture or structure which it has beencompelled to assume from the start. Thus, not only a. mere increase ofresistivity against influences tending to disturb the natural fibrousstructure of the material is involved, but also an additionalstabilizing capacity of the deformed fibrous material.

The products according to the invention are distinguished by acalender-finish which is rendered absolutely fast to washing by beingfixed by impregnation with artificial resins that are fast to light andpractically odorless and colorless. As resins qualifying for thispurpose, carbamide-aldehyde resins may be mentioned or else a mixture ofurea and thio-urea condensation products. Alternatively, the artificialresin used for the impregnation may be combined with sizing, softening,matting or filling materials or with dyestuffs.

By means of the method according to the invention a lasting finish canbe applied to a textile, for example, by previously impregnating thefabric with a solution of a resin or a mixture of resins adapted to behardened in combination with suitable catalyzers, softening or fillingmaterials, dyestuffs or similar auxiliary materials commonly used in thetextile industry as wetting materials, and thereupon subjecting thefabric in a moist or in dry condition to a calendering at a propertemperature. The thusly treated fabric is then hardened in a knownmanner, preferably by a proper treatment by heat. Advantageously, thefabric is subsequently soaped, washed and dried. The effects thusobtained withstand wet treatments and washing without losing thecalender effect irrespective of whether, as the case may be, stamping,feel, gloss, moire, wave, plait, beetle or other effects are involved.Furthermore, this mode of procedure involves the surprising result thatspots arising in the fabric due to drops of certain liquids gettingthereon is no longer to be feared, whereas the finish obtained by meansof the hitherto known methods was completely destroyed by dulling thefinish, or eliminating the stamping effect on the same. The fabricsobtained in this manner can be dyed in normal manner without eliminatingthe finish.

It is obvious that the substance to be hardened can be applied to thefabric in any other proper manner instead of by impregnation, forexample by spraying, printing or the like.

After a brief calendering has been applied thereto, the fabric issubmitted to a final heat treatment in order to harden theresincompletely. V

The previously mentioned modes of procedure, viz. moire, wave, stamping,crepe, lucid gloss, matted gloss, silk lustre, similar imitationmercerizing surface treatment effect and the like are also classified ascalender finishing. A finish giving a, softer or harder feel can beobtained depending on the substance chosen for the im pregnation. It isobvious that the substance used for the impregnation can be modified bythe addition of known sizing materials, as starch, dextrin, British gumetc. In this way the final finish can be varied within wide limits.

The hardening can be effected to advantage in a drying chamber thetemperature of which can be controlled, or else on drying cylinders orin calenders or the like. The temperature at which the hardening iseffected and the duration of the hardening process depend largely on thechemical nature'of the resin, the presence of catalyzers and so on.

As resins adapted to be hardened, particularly artificial resins of thetype of carbamide resins are extremely well qualified in this respect onaccount of being colorless, highly fast to light and adapted to behardened in an easily variable manner. Furthermore, these resins do notcause fading during storage of the textiles, which is of greatimportance. Among these carbamide resins the urea and thin-ureacondensation products and mixtures of the same of a lower condensationphase are particularly well suited, especially if soluble in water. Allthese resins can naturally be applied in combination with catalyzers,for influencing the hardening, with dyestuffs, softening, filling,matting, wetting or other materials commonly used in the textileindustry.

The method described can be applied to textile articles such as fabricsor meshed goods of any kind made of any suitable materials, as forexample cotton, linen, hemp, ramie, artificial silk composed ofcellulose or cellulose derivatives, or mixed fabrics and so forth. ,Alsofabrics that are mercerized or improved by treatment with acid or lye orother swelling agents enter into question. The applicability of thenovel method to cotton and artificial silk and to fabrics con tainingboth of these materials is of particular importance. Very beautifuleffects can be obtained also on printed fabrics by means of knowncalender treatments.

Example 1 A mixed fabric composed of artificial silk and cotton isimpregnated following the bleaching and dyeing with a 20% aqueoussolution of carbamide resin containing 0.5% of tartaric acid and thenthe slightly dried fabric is passed through a stamping calender heatedto about 150 C. By thispassage the pattern is distinctly stamped intothe fabric. Thereupon the fabric is hardened in a drying chamber whichis kept heated to 110 C. for about to minutes. On the subsequent washingand drying the stamping pattern is left perfectly intact and remainspermanently fast to washing.

Example 2 A cotton muslin fabric is impregnated in the manner describedin Example 1 and subjected to a hot calender treatment in a moistcondition to obtain a gloss effect. After the hardening, which iseffected as described in the preceding example, the fabric is soaped,rinsed and dried. The highly lucid finish thus obtained is fast towashing and perfectly immune to the effect of drops of certain liquids.

Example 3 A fabric of artificial silk is subjected in impregnatedcondition to a calender treatment for matting the same and furthertreated as specified in Example 1. The thus obtained matting andstiffening remains incorporated in the fabric after the wash.

Example 5 A cotton fabric which is impregnated with a 25% solution ofdimethyl-urea is subjected, after being slightly dried, to a calendertreatment for obtaining a gloss effect and repeatedly passed to the hotroller of the calender through the chasing apparatus until the hardeningis completed. The finishing treatment is applied to the fabric asexplained above.

Example 6 A satin fabric is printed with a printing paste which containsper kilogram of weight, in addition to the usual thickening materials,225 grams of dimethylol-urea and '75 grams of thicurea together with 2%of boric acid (as regards the total amount of dimethylol-urea plusthicurea). The slightly dried fabric is then subjected to a hot calendertreatment to obtain a high lucidity, finally hardened, washed and dried.

The thus treated fabric displays a damask-effect, the printed portionsof the fabric being highly lucid, whereas the non-printed portions aredulled. This result is due to the fact that, on

washing, the calender finish effect is removed from the unprintedresin-free portion of the fabric but is unaltered on the printedportion. If desired, the fabric can be subsequently dyed.

Example 7 A cotton voile which is imprinted with vat dyestuffs in amanner fast to washing is impregnated with a solution which contains 20%of a ureaformaldehyde condensation product soluble in water togetherwith 0.5% of salicylic acid acting as a catalyzer. The precautiouslydried fabric is then subjected to a hot treatment in a stampingcalender, and thereupon finally hardened at 130 C. for 5 minutes. Afterthe soaping, washing and drying afabric is obtained which displays abeautiful novel combination effect of color printing and reliefstamping.

In my copending application Serial No. 746,933, filed October 4, 1934,for Methods of rendering textilesresistive against shrinking and productthereof, I have disclosed and claimed the production of non-shrinkfabrics by impregnation with certain hardenable resins, tensioning thematerial, and hardening the resin while under tension.

In my application Serial No. 193,211, for the Production of textilefabrics in formed printed patterns, filed February 28, 1938, which is adivision of the present application, I have claimed the embodiment ofthis invention in which the heat hardenable resin is applied to thetextile by printing so that the permanent wash-fast calender effectoccurs only on the printed portions.

What I claim is:

1. Process of producing calender finishes on cellulose textile fabrics,comprising impregnating the fibers of the fabric with an aqueouscarbamide resin-forming solution, capable of reaction to increase theresistivity of fibers impregnated therewith against fiexion andcontaining an acid catalyst; drying the fibers slightly or to a moistcondition; and then changing the form and relative disposition of thefibers to impart to the slightly moist fabric an ornamental texture bymeans of a calender heated to about 150 0.;

and thereupon hardening the resin completely upto the final state inwhich the calender finish becomes permanently fast to washing by heatingto 110 C. for about 5-10 minutes.

2. Process of producing calender finishes on cellulose textile fabrics,comprising impregnating the fibers of the fabric with an aqueousresinforming solution, capable of reaction to increase the resistivityof fibers impregnated therewith against flexion; drying the fibersslightly or to a moist condition; and then changing the form andrelative disposition of the fibers to impart to the slightly moistfabric an ornamental texture by means'of a heated calender; andthereupon subiecting the fabric to a heat treatment'at a temperature andfor a period of time that will harden the resin completely upto thefinal state without deterioration oi the fabric, and in which thecalender finish becomes permanently fast to washing.

3. 'Ihe product of the process of claim '2 being a cellulose textilefabric with a calender finish effect fixed by heat hardened resin andcharacterized by the quality that the calender finish is substantially.permanent and will withstand washing with soap and water withoutsubstantially losing the calender effect.

CHRISTIAN BENER.

